Dolby TrueHD Lossless Audio

Enjoy the best sound possible for movies, music, and TV shows with Dolby TrueHD lossless audio built into your home theater, music, movies, and other content.

Dolby TrueHD Benefits

Lossless Audio

Unlike most audio formats, Dolby® TrueHD is 100 percent lossless. This means that what you hear is bit-for-bit identical to the master recording.

Multichannel Sound

With support for up to 7.1 channels of high-definition audio, Dolby TrueHD provides the most authentic surround sound experience available for your home theater.

 
Blu-ray at Its Best

Dolby TrueHD fully exploits the potential of Blu-ray™ by enabling the maximum audio fidelity possible on these discs and bringing you one step closer to the source.

Ready for Tomorrow

Capable of delivering 16 channels of top-quality audio, Dolby TrueHD has room to expand as formats add new channels in the future.

The Authentic Lossless Audio Experience

A filmmaker can spend years working to make every detail of a movie perfect, and this includes the audio. Dolby TrueHD ensures that what you hear at home is completely accurate to the artist's vision—not an approximation or a recreation, but the full audio experience. Every detail of the original recording is preserved because Dolby TrueHD reproduces audio bit-for-bit identical to the studio master.

Dolby TrueHD accomplishes this using a suite of highly sophisticated compression technologies. These enable 100 percent lossless audio in files half the size of uncompressed pulse-code modulation (PCM). What this means for you is the best possible sound from Blu-ray Discs™ and streamed or downloaded sources.

 

A Boost to Home Theater Performance

Most movie and TV soundtracks are recorded at 48k. Unfortunately, the 48k recording process can introduce an unnatural harshness or edginess to the sound during the conversion from analog to digital. Dolby TrueHD corrects this problem by applying higher sample rates and increased playback quality through an advanced apodizing filter.

On Blu-ray, Dolby TrueHD supports up to eight full-range channels of 96 kHz/24-bit audio and six full-range channels of 192 kHz/24-bit audio. It also features advanced 96k upsampling to produce the highest-quality Blu-ray audio from material originally recorded at 48k.

The result: you experience entertainment as it was meant to be heard.

 

Dolby TrueHD Lossless Audio Advanced Features

  • Transfers data at bit rates of up to 18 Mbps for unmatched sound quality
  • Delivers up to 16 channels of pristine audio at studio-master quality
  • Maintains consistent dialogue levels when changing between Dolby TrueHD and Dolby Digital programming
  • Includes dynamic range control, enabling reduced peak volume levels without loss of overall sound quality—ideal for listening without disturbing others
  • Provides superior 7.1 downmix overload detection and protection
  • Gives the Blu-ray content creator the ability to include a companion Dolby Digital (640 kbps) 5.1-channel theatrical mix on 7.1-channel Dolby TrueHD titles

Dolby TrueHD Lossless Audio for Professionals

Dolby TrueHD makes it easier than ever for content creators and equipment manufacturers to deliver 100 percent lossless audio to the home theater.
 

Dolby TrueHD for Content Creators

Whether you're creating movies, TV shows, or music, Dolby TrueHD captures every audio detail with absolute accuracy. Now audiences at home can experience the full impact of your work.
 

Control the Audio Experience with Metadata

  • Since a single Dolby TrueHD stream can contain up to three separate mixes—a 7.1-channel mix, a 5.1-channel mix, and a two-channel stereo mix—you can tailor each one for optimum listening on any playback system.
  • Dynamic range control enables reduced peak volume levels without impacting overall sound quality. It's ideal for late-night viewing.
  • The 96k upsampling process applies higher sample rates and increased playback quality through an advanced apodizing filter that masks undesirable digital artifacts in 48k material. The upsampling takes place before Dolby TrueHD encoding.
  • For stereo listening, you can enable playback from the original multichannel source using downmixing or provide an independent stereo mix incorporated into the Dolby TrueHD bitstream.
  • Dialogue normalization (dialnorm) maintains consistent volume levels when switching between Dolby TrueHD and Dolby Digital or Dolby Digital Plus™ programming.
  • You decide whether to employ 96k upsampling in your content. The process is designed to improve 48k audio files and is not needed for native 96k material.

Dolby TrueHD for Equipment Manufacturers

With a unique 96k upsampling process and the power of Dolby metadata, Dolby TrueHD can differentiate your products from the competition. It unlocks the full potential of Blu-ray, and allows audiences to hear every detail of their favorite entertainment.
 

Upsampling and Metadata: A Closer Look

  • The advanced 96k upsampling in Dolby TrueHD enables an A/V receiver or Blu-ray Disc player to perform postprocessing (such as equalization and bass management) at higher sampling frequencies.
  • Although the upsampling increases file size and data rates, the optional Dolby Mapping (noise-shaping) feature, specifically designed for Dolby TrueHD, minimizes or eliminates these increases.
  • Downmixing allows a content creator to enable stereo playback from the original multichannel source or to provide an independent stereo "artist's mix" that's incorporated into the Dolby TrueHD bitstream.
  • By applying the upsampling in software, Dolby TrueHD creates content that’s compatible with all Blu-ray players and all A/V receivers with 96k digital-to-analog converters (DACs). It doesn't add any computing burden in playback.
  • Dynamic range control enables reduced peak volume levels without impacting overall sound quality. It's ideal for late-night viewing.
 

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Dolby TrueHD Specifications

  • Leverages interchannel correlations to reduce data rates for lossless matrixing and more efficient downmixing

  • Employs decorrelation to take advantage of the predictive nature of audio

  • Allows fewer bits to be assigned for commonly occurring values within the data stream for a more efficient coding process using Huffman (entropy) coding

  • Smooths the encoded data rate with managed FIFO buffering throughout transmission

Sampling frequency

44.1 kHz to 192 kHz

Sampling rate

Variable bit rate; CBR rendering for transport over HDMI®

Word length

Up to 24 bits

Blu-ray Disc channel support

Up to eight channels of 24-bit/96 kHz audio; designed to be expandable should the Blu-ray Disc standard adopt additional channels

Two- to six-channel support

Up to 24-bit/192 kHz

Maximum bit rate

Up to 18 Mbps on Blu-ray Disc

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Hardware

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Customer Support

Dolby Business Partners

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Get help about professional products or services.

Dolby Support